Biotechnology: Cloning, tissue culture and GM crops

Bt brinjal, carrying the event EE-1 with the cry1Ac gene against the fruit and shoot borer, was developed by Mahyco. The GEAC recommended its environmental release on 14 October 2009. Faced with protests from farmers' groups, scientists and several State governments, the then Environment Minister held public consultations in several cities and, on 9 February 2010, announced a moratorium on its release until independent studies established its safety to the satisfaction of both the public and professionals. That moratorium has never been lifted, so Bt brinjal is not approved for cultivation in India. Ironically, neighbouring Bangladesh approved Bt brinjal varieties built on the same Indian event in 2013 and has grown them since 2014. The brinjal, it seems, needed a visa rather than a gene.

HTBt cotton stacks the Bollgard II insect-resistance genes with a gene for tolerance to glyphosate (the Roundup Ready Flex trait). It has not been approved for commercial cultivation in India. The GEAC has repeatedly examined the application, reconstituted an expert committee in 2025 and asked for more data in 2026, but no approval has been granted. Meanwhile, unauthorised HTBt seed has spread through informal channels in Maharashtra, Telangana, Gujarat and other States, because it lets farmers spray glyphosate to kill weeds instead of paying for manual weeding. Enforcement agencies have seized such seed under the Seeds Act and the Environment (Protection) Act. So the honest summary is 'not approved, but not absent'. Weeds don't read notifications, and neither, it seems, do some seed dealers.

Flavr Savr, developed by the Californian company Calgene, was approved by the US Food and Drug Administration in 1994. It carried an antisense copy of the gene for polygalacturonase, an enzyme that breaks down pectin in the cell walls as the fruit ripens. By reducing the enzyme, the fruit softened more slowly, so it could be left on the vine longer to develop flavour and still survive shipping. It is the classic example of antisense or gene- silencing technology in agriculture, the same family of methods that later gave us RNA interference for pest control. Commercially, it did not last long, because of production and cost problems, and it was withdrawn within a few years. A tomato that kept fresh longer could not keep its company alive for long, which is a lesson in business, not biology.

All three are correct. The GEAC cleared the environmental release of Bt brinjal on 14 October 2009, before the Union government imposed a moratorium in February 2010. The technology then crossed the border: the Bangladesh Agricultural Research Institute, working with Cornell University under a USAID-backed programme, back-crossed Mahyco's event EE-1 into local varieties, Bangladesh's biosafety committee approved four of them on 30 October 2013, and the first seedlings were handed to 20 farmers on 22 January 2014. The pest in both cases is the brinjal fruit and shoot borer (Leucinodes orbonalis), a moth larva that tunnels into shoots and fruits and drives farmers to spray very frequently. That is why Bt brinjal promised such a large cut in pesticide use, and why it became the test case for food crops in South Asia.

A promoter is a stretch of DNA in front of a gene where RNA polymerase binds to start transcription; it decides when, where and how strongly the gene is expressed. The CaMV 35S promoter comes from the cauliflower mosaic virus, a plant virus, and it is a strong, largely constitutive promoter: it keeps the gene switched on in most tissues for most of the time. That is why it has been used in many first-generation GM plants and why GM detection kits often screen for 35S sequences in food and seed. Statement 3 confuses two kinds of tools. Restriction enzymes such as EcoRI are proteins that cut DNA at specific palindromic sites; a promoter is a piece of DNA, not an enzyme, and it cuts nothing. One is a switch, the other is a pair of scissors; neither should be mistaken for the other in an exam hall.

The full name gives most of the answer: the Rules for the Manufacture, Use, Import, Export and Storage of Hazardous Micro-organisms, Genetically Engineered Organisms or Cells, 1989. They were notified on 5 December 1989 using powers under sections 6, 8 and 25 of the Environment (Protection) Act, 1986, and came into force in 1993. As the title shows, they reach beyond GM crops to hazardous micro-organisms, whether modified or not. Rule 4 sets up six competent authorities at several levels: the RDAC, RCGM and IBSC at the advisory and research end, the GEAC at the environmental-release end, and the State Biotechnology Coordination Committee and District Level Committee for monitoring on the ground. So the system is deliberately multi-level, and statement 3 fails.

Glyphosate kills plants by blocking the enzyme EPSPS, which is needed to make aromatic amino acids through the shikimate pathway. The cp4-epsps gene, taken from an Agrobacterium strain, codes for a form of the enzyme that glyphosate cannot block, so the plant keeps growing while weeds around it die. In HTBt cotton (event MON 88913 stacked with the Bollgard II event MON 15985), this trait is combined with the cry1Ac and cry2Ab genes, so statements 1 and 3 are right. Statement 2 is wrong: the GEAC has not approved HTBt cotton. In 2025 the committee only reconstituted an expert panel to re-examine the data, and in 2026 it sought more data on performance under Indian conditions. The spread of illegal seed shows the demand, but demand is not a licence; otherwise, every traffic jam would count as permission to drive on the footpath.

Pairs 1, 2 and 3 are correct. Bt brinjal carries cry1Ac against the brinjal fruit and shoot borer. DMH-11 uses the barnase-barstar system to create male sterility in one parent and restore fertility in the hybrid, which makes commercial hybrid seed possible in a self-pollinating crop. Golden Rice makes beta-carotene, which the body converts into vitamin A. Pair 4 is wrong: the Flavr Savr tomato was engineered for delayed softening, through suppression of the cell-wall enzyme polygalacturonase, not for drought tolerance. Abiotic-stress traits such as drought tolerance came much later in GM crops, for example in some maize and wheat events abroad. Matching questions of this kind reward a simple one-line memory card for each crop: pest, sterility, vitamin, shelf life. Four cards, four seconds.

Statements 2 and 3 are correct (b). Statement 2 is right: GenomeIndia (2020) is funded by the Department of Biotechnology. Statement 3 is right: it sequenced 10,000 genomes from many Indian communities to build a catalogue of the country's genetic variation, and the data was released in 2025. Statement 1 is wrong: the international Human Genome Project was a separate effort that ended in 2003. So options (a), (c) and (d) fail.

Notice the uses: finding gene variants behind diseases common in India, such as sickle cell and thalassaemia, and building personalised medicine. The data is stored at the Indian Biological Data Centre in Faridabad. A larger follow-up aims to sequence one million genomes.

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All three are correct (d). Mycorrhiza is a partnership between a fungus and plant roots. The fungal threads extend the absorbing area of roots far into the soil, helping the plant take up water and resist drought (1). They help plants tolerate extremes of pH, salinity and heavy metals in poor soils (2). They also protect roots against soil pathogens by forming a barrier and competing with them (3). This is why mycorrhizal inoculants are used to rehabilitate degraded sites such as mine spoils. So (a), (b) and (c) leave out real benefits.

Notice the main benefit: mycorrhiza greatly improves phosphorus uptake. About 80% of land plants form such partnerships. TERI in India developed mycorrhizal biofertilisers for wasteland reclamation. Trap: all three effects are documented.

Answer as per the official UPSC answer key.

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